356 RWHP TPI 310 Build
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Re: 356 RWHP TPI 310 Build
"WOT timing is 30* @ 4,000 rpm"
I guessing that you mean that WOT timing is 30 deg greater than the base timing.
So the total timing is 30 + (base)?
I guessing that you mean that WOT timing is 30 deg greater than the base timing.
So the total timing is 30 + (base)?
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Re: 356 RWHP TPI 310 Build
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Re: 356 RWHP TPI 310 Build
I genuinely want to believe this, I really do, but I gotta be honest. This is a tough pill to swallow. You're coming very close to 100hp/liter. There are extremely few engines that have hit that naturally aspirated. The first two that come to mind is the Honda B16 in the civic Si, and many of the new K-series engines. These engines are dual overhead cam, variable valve timing techno wizzards. From oil cap to drain plug they are designed with efficiency in mind. You have a 2 valve small block chevy from 1955. You have eclipsed even the acclaimed LSx engines. I just can't get my mind wrapped around this yet.
The ONLY thing I can think of to explain this is that your intake may be hitting its perfect peak resonance at your peak torque and HP. This would have to be a result of perfect cam timing to interface with the resonant frequency of your intake components. This engine has the VE of DOHC performance engines, inertial supercharging is the only way I can think of to overcome the loses in the cylinder heads.
The ONLY thing I can think of to explain this is that your intake may be hitting its perfect peak resonance at your peak torque and HP. This would have to be a result of perfect cam timing to interface with the resonant frequency of your intake components. This engine has the VE of DOHC performance engines, inertial supercharging is the only way I can think of to overcome the loses in the cylinder heads.
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Re: 356 RWHP TPI 310 Build
i'm sorry, but i cannot buy this neither... that's almost what i'm making in my 305
#55
Re: 356 RWHP TPI 310 Build
hey 86z im in ct also i used to have a supercharged tpi ,ran good but could never get it to run perfect because i couldnt get any1 who wanted to build a prom for a supercharged tpi. this was a few years back. i now have a 91 z an wanna go back to supercharge. my ? is do u know any local tuners / chip burners who would help out tuning it ,if u dont mind who tuned yours thanks.
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Re: 356 RWHP TPI 310 Build
The timing numbers are so low that they look like they are basically for an iron headed 350. A stock 305 bin shows WOT 30 deg + 6 deg in PE = 36 degs total.
I'm just wondering why you are using so little total advance on a highly modified engine.... I've always read that a cammed engine wants more timing than a stock one.
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Re: 356 RWHP TPI 310 Build
As for the numbers, eh. Even if they're a bit optimistic, he's still done a great job given the quality of the torque curve. He's clearly put a lot of time and effort into this tune.
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Re: 356 RWHP TPI 310 Build
hey 86z im in ct also i used to have a supercharged tpi ,ran good but could never get it to run perfect because i couldnt get any1 who wanted to build a prom for a supercharged tpi. this was a few years back. i now have a 91 z an wanna go back to supercharge. my ? is do u know any local tuners / chip burners who would help out tuning it ,if u dont mind who tuned yours thanks.
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Re: 356 RWHP TPI 310 Build
I recently dyno'd my 305 TPI project that is currently in the 1983 G20 Van. After many builds, I have come to respect the little 305 and what it is capable of. When properly built they can turn out some HP.
http://store.summitracing.com/partde...5&autoview=sku (Modified to my needs, ported and siamesed)
http://store.summitracing.com/partde...5&autoview=sku (Is the same as this edelbrock one, I ported it up nicely).
The heads were setup for .510" lift and the appropriate springs were setup for the camshaft specs.
http://store.summitracing.com/partde...5&autoview=sku (Modified to my needs, ported and siamesed)
http://store.summitracing.com/partde...5&autoview=sku (Is the same as this edelbrock one, I ported it up nicely).
The heads were setup for .510" lift and the appropriate springs were setup for the camshaft specs.
If you don't mind a couple of questions... Can you tell me more about the changes you made to your SLP runners? How far down did you cut out the divider?
Much change to the Vortec intake base?
Did you go with screw in rocker arm studs? It would seem so with a strong spring and 6k RPM.
The vacuum to the crank case is interesting. Can you tell us some more about that?
Thanks, Scot
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Re: 356 RWHP TPI 310 Build
I have been starting to collect parts for a 305 build that is very similar to yours. 305 roller block, KB 143 flat top pistons (+0.030), 059 vortec heads, ZZ4 cam, Vortec TPI intake with SLP runners. Also a set of Comp Cams 1418-16 1.6 roller tipped rockers.
If you don't mind a couple of questions... Can you tell me more about the changes you made to your SLP runners? How far down did you cut out the divider?
Much change to the Vortec intake base?
Did you go with screw in rocker arm studs? It would seem so with a strong spring and 6k RPM.
The vacuum to the crank case is interesting. Can you tell us some more about that?
Thanks, Scot
If you don't mind a couple of questions... Can you tell me more about the changes you made to your SLP runners? How far down did you cut out the divider?
Much change to the Vortec intake base?
Did you go with screw in rocker arm studs? It would seem so with a strong spring and 6k RPM.
The vacuum to the crank case is interesting. Can you tell us some more about that?
Thanks, Scot
The changes to the base weren't too drastic, just a cleanup and mild porting to match up with the heads and runners.
I DID use screw in studs on the heads. They are cheap insurance for what I am doing.
Vacuum to the crankcase is nothing new. Racers have been using vacuum pumps and converted smog pumps for some time now. I am using a belt drive emissions air pump reconfigured to pull air from the crankcase. It pulls about 7-9 in/hg on the crankcase which helps cut windage and allows the rings to seal better at higher rpms. Too much positive crankcase pressure is known to cause ring flutter which keeps them from sealing properly on the downward intake stroke and dilutes the intake charge.
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Re: 356 RWHP TPI 310 Build
Thanks for the response.
I noticed for the rings listed that Summit says gapless second ring. Why not a gapless 1st ring? I bought KB's, and KB says to run a wide gap on the 1st ring. The gapless style seems like a better answer than a wide gap 1st ring.
Thanks, Scot
I noticed for the rings listed that Summit says gapless second ring. Why not a gapless 1st ring? I bought KB's, and KB says to run a wide gap on the 1st ring. The gapless style seems like a better answer than a wide gap 1st ring.
Thanks, Scot
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Re: 356 RWHP TPI 310 Build
nice build... so no nos?? wuts your compression? also, i thought the stock throttle body was 48mm not 46
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Re: 356 RWHP TPI 310 Build
Last years Engine Masters competition (EMc) had a 305 that dynoed approx 390 fwhp on an engine dyno. IIRC the owner used GM alum Fastburn heads (large port conventional-flow-cooling equivalents of the aluminum LT4 factory head) and a 236 deg cam IIRC, and the usual carb + headers.
Fast355's 305 engine: ported iron 059s with bigger valves will be a better burner of fuel than the Fastburn heads used in EMc, and they will flow just about as well..... and with the smaller port volume (170 cc vs 215 cc), the flow speed will be much better so the swirl and turbulence will be much better. So Fast355 will make better power with less need for spark advance. The port fuel injection will also allow much better tuning across the full range of rpms at WOT than the carbed EMc 305. So Fast355's assumed 418 fwhp (15% drivetrain loss via 356 rwhp) compares sensibly with the 305 build in the EM.
Finally, there is a long sticky thread in the TPI section here at TGO showing the comparison of approx 9 versions of TPI intakes and one non-TPI intake manifold, as used on a built 383. The worst TPI setup was the stocker (duh) and IIRC it made around 420 hp. So the stock TPI intake can move enough air to make 420+ fwhp using a big cam in a 383..... so it stands to reason that better flowing aftermkt TPI runners + Vortec lower base intake can move the same air while spinning at a higher rpm in a smaller engine (305), even with the small cam. You don't need a big cam to make big power if the intake & exh flow losses are small and the combustion (burn) is ideal.
Fast355's 305 engine: ported iron 059s with bigger valves will be a better burner of fuel than the Fastburn heads used in EMc, and they will flow just about as well..... and with the smaller port volume (170 cc vs 215 cc), the flow speed will be much better so the swirl and turbulence will be much better. So Fast355 will make better power with less need for spark advance. The port fuel injection will also allow much better tuning across the full range of rpms at WOT than the carbed EMc 305. So Fast355's assumed 418 fwhp (15% drivetrain loss via 356 rwhp) compares sensibly with the 305 build in the EM.
Finally, there is a long sticky thread in the TPI section here at TGO showing the comparison of approx 9 versions of TPI intakes and one non-TPI intake manifold, as used on a built 383. The worst TPI setup was the stocker (duh) and IIRC it made around 420 hp. So the stock TPI intake can move enough air to make 420+ fwhp using a big cam in a 383..... so it stands to reason that better flowing aftermkt TPI runners + Vortec lower base intake can move the same air while spinning at a higher rpm in a smaller engine (305), even with the small cam. You don't need a big cam to make big power if the intake & exh flow losses are small and the combustion (burn) is ideal.
Last edited by kdrolt; 06-25-2008 at 03:50 PM.
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Re: 356 RWHP TPI 310 Build
WOW....
This is some really good food for thought.
I have an '85 Z28 with a modded 305 myself.
I've heard the naysayers for years.....and while yes, it's hard to beat cubic inches, the more someone tells me I CAN'T do it, the more it makes me want to.
Now, mine is a carb'ed setup, but this makes me confident that I can reach respectable HP #'s with my mini-mouse.
This is some really good food for thought.
I have an '85 Z28 with a modded 305 myself.
I've heard the naysayers for years.....and while yes, it's hard to beat cubic inches, the more someone tells me I CAN'T do it, the more it makes me want to.
Now, mine is a carb'ed setup, but this makes me confident that I can reach respectable HP #'s with my mini-mouse.
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Re: 356 RWHP TPI 310 Build
After staring at the 305 head pictures for a while, I see that the area around the intake valve has been unshrounded. Did you bring this out to match the edge of the cylinder wall? Was it done freehand, or on a machine? It looks nicely done...
Scot
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Re: 356 RWHP TPI 310 Build
Man that motor sounds healthy, wish my 305 sounded so good, im impressed everybody always trashes 305's, way to stick it to em.
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Re: 356 RWHP TPI 310 Build
How do you make a smog pump into a vacuum pumP?
id like to do that...
thank you
nice motor by the way i hope to be up there when mine is done...
id like to do that...
thank you
nice motor by the way i hope to be up there when mine is done...
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Re: 356 RWHP TPI 310 Build
once again i wish i lived closer to you, just to get the inspiration, or tuning insight even haha!
it makes perfect sense to me that a more efficient, smaller engine can make more power than a heavier less efficient engine.
i think people get a little too carried away with going to big on heads. just because your heads flow a peak of 260cfm who cares..... how often are your valves open .600 flowing that?
the part that realy makes all the difference is the area under the curve which you clearly increased to its fullest.
there is no point in overcamming an engine because once again you are killing the area under the curve. I think what you posted is very plausible and the data is all here to prove it.
ps. you should move to ohio so you can tune mine lol . nice job again and thank your for all your insight.
it makes perfect sense to me that a more efficient, smaller engine can make more power than a heavier less efficient engine.
i think people get a little too carried away with going to big on heads. just because your heads flow a peak of 260cfm who cares..... how often are your valves open .600 flowing that?
the part that realy makes all the difference is the area under the curve which you clearly increased to its fullest.
there is no point in overcamming an engine because once again you are killing the area under the curve. I think what you posted is very plausible and the data is all here to prove it.
ps. you should move to ohio so you can tune mine lol . nice job again and thank your for all your insight.
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Re: 356 RWHP TPI 310 Build
once again i wish i lived closer to you, just to get the inspiration, or tuning insight even haha!
it makes perfect sense to me that a more efficient, smaller engine can make more power than a heavier less efficient engine.
i think people get a little too carried away with going to big on heads. just because your heads flow a peak of 260cfm who cares..... how often are your valves open .600 flowing that?
the part that realy makes all the difference is the area under the curve which you clearly increased to its fullest.
there is no point in overcamming an engine because once again you are killing the area under the curve. I think what you posted is very plausible and the data is all here to prove it.
ps. you should move to ohio so you can tune mine lol . nice job again and thank your for all your insight.
it makes perfect sense to me that a more efficient, smaller engine can make more power than a heavier less efficient engine.
i think people get a little too carried away with going to big on heads. just because your heads flow a peak of 260cfm who cares..... how often are your valves open .600 flowing that?
the part that realy makes all the difference is the area under the curve which you clearly increased to its fullest.
there is no point in overcamming an engine because once again you are killing the area under the curve. I think what you posted is very plausible and the data is all here to prove it.
ps. you should move to ohio so you can tune mine lol . nice job again and thank your for all your insight.
Cylinder head selection will MAKE or BREAK your combination. Selecting and setting up the heads is even more important than selecting the cam. The cam has to match the heads, intake, exhaust, and short block. You also want to eek out ALL they dynamic compression ratio you can. It is also benifiical to get the exhaust out and keep the intake charge as un-contaminated as you can.
I have some pictures of the intake runners before modification and ported plenum I was running.
Last edited by Fast355; 05-22-2009 at 10:02 PM.
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Re: 356 RWHP TPI 310 Build
Finally, I stole this picture from another post from a member (cannot remember who) on here. Its a 083 350 TPI head with 1.94/1.50 valves on a stock bore 305. On a .030" over 305 there is even more clearance between the bore and intake valve. The 1.6" exhaust valve clears easily as well. I unshrouded the top of the bores as well as the cylinder head, both to more closely match the intake bores. The top of the cylinder bores typically have plenty of meat to withstand this, but I would do it before doing the rest of the machine work on the block in case by some bizarre circumstance you hit water.
I know I will get some grief here. This is the only picture I have of the 059 intake bowls. NO these heads are not swirl ports, they have a slight swirl vane in the bottem that is NOTHING like the TBI swirl ports. The intake ports are the same as the L31, down to the vane leading up to the valve guide, they just have the short swirl inducing ramp on the high velocity side of the port to help generate swirl. I still obtained 250 CFM @ .500" lift from these heads through a 1.94" intake valve and all the swirl you could need to get a good burn. Notice I had already machined on the chambers.
Here is a conventional non vortec port and a TBI swirl port for comparison purposes.
I know I will get some grief here. This is the only picture I have of the 059 intake bowls. NO these heads are not swirl ports, they have a slight swirl vane in the bottem that is NOTHING like the TBI swirl ports. The intake ports are the same as the L31, down to the vane leading up to the valve guide, they just have the short swirl inducing ramp on the high velocity side of the port to help generate swirl. I still obtained 250 CFM @ .500" lift from these heads through a 1.94" intake valve and all the swirl you could need to get a good burn. Notice I had already machined on the chambers.
Here is a conventional non vortec port and a TBI swirl port for comparison purposes.
Last edited by Fast355; 05-22-2009 at 10:04 PM.
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Re: 356 RWHP TPI 310 Build
Fast355, as I often am in these discussions, I totally believe the numbers, more so, I’m surprised that we have some very experienced people here that seem to have a hard time believing them (that and I just got done reading the “Quest for a better flowing TPI” thread, which seems to lean the opposite way, reading most of their posts over there makes it sound like this should be totally impossible). Not that you really need it anyway, but unfortunately, I doubt that me agreeing with you helps at all, since I’m usually the one at your end, and even at the track have had monkey’s crawling all over the car trying to figure out “where’s the supercharger?” or “where did you hide the NOS...?”
That said, few comments/questions, comments first:
- Weird, numbers… well yea, try racing something the size of a bus, shaped like a brick that weighs 2000# more than an f-body… It’s almost exactly the same size, shape, gearing, drivetrain as my Blazer had, and my numbers had the same weird skew to them.
- I’m not sure why people expect such a big difference between a LS based engine and an SBC with nearly identical numbers… both are using a fast burn chamber, both have the same cooling and are very similar in design… the biggest difference is the 15* Vs 23* valves, and that’s more an airflow difference than anything else, and let’s face it, your combination is only making enough HP to use about 200cfm of airflow or so, so you’ve got more flow than you need. Honestly, I’m a bit surprised that you’re doing it with SLP runners rather than stockers.
- I like the torque and HP curves… they’re _exactly_ what would be predicted if you do the math on a TPI intake… your cam choice and it’s tighter LSA doesn’t interfere with the natural powerband of the TPI, which is basically fat in the middle and keeps going till you run out of air (your combination that should be somewhere ~6500 from what I can tell). As I keep saying, if you want monstrous fat low end, say in the 2000rpm range, than you really need something different than a TPI
Questions:
- How close are you on the detonation front? I’ve run combinations close to that before and always chickened out before pushing it quite that far, either a pulling back on the compression or finding a little more overlap to decrease dynamic compression a little for a little extra detonation control. I’ve always regretted it also, since I’ve never had detonation issues with anything I’ve tried like this, a few iron headed engines pushing or in the low 10:1 compression range which seem to run fine even on 87…
- What are those cylinder heads painted with?
- Huh??? The only thing I can figure is that you changed what you’re doing between responses?
Along those lines I have a smog pump off of an 80’s ford bronco that I modified for fittings that I’m planning on using the same way, I’m hoping that it is going to be close to a bolt in to the stock smog pump bracket, but I’m debating if I should try it or find another since the front bearing bore was a bit messed up and I had to use some JB weld to get a new bearing to seat correctly. What vacuum relief valve are you using?
- Do you actually have the valves unshrouded or are those just cuts from cutting the seats for the larger valves?
- Someone else already asked, but I didn’t see a response: what datalogger is that?
That said, few comments/questions, comments first:
- Weird, numbers… well yea, try racing something the size of a bus, shaped like a brick that weighs 2000# more than an f-body… It’s almost exactly the same size, shape, gearing, drivetrain as my Blazer had, and my numbers had the same weird skew to them.
- I’m not sure why people expect such a big difference between a LS based engine and an SBC with nearly identical numbers… both are using a fast burn chamber, both have the same cooling and are very similar in design… the biggest difference is the 15* Vs 23* valves, and that’s more an airflow difference than anything else, and let’s face it, your combination is only making enough HP to use about 200cfm of airflow or so, so you’ve got more flow than you need. Honestly, I’m a bit surprised that you’re doing it with SLP runners rather than stockers.
- I like the torque and HP curves… they’re _exactly_ what would be predicted if you do the math on a TPI intake… your cam choice and it’s tighter LSA doesn’t interfere with the natural powerband of the TPI, which is basically fat in the middle and keeps going till you run out of air (your combination that should be somewhere ~6500 from what I can tell). As I keep saying, if you want monstrous fat low end, say in the 2000rpm range, than you really need something different than a TPI
Questions:
- How close are you on the detonation front? I’ve run combinations close to that before and always chickened out before pushing it quite that far, either a pulling back on the compression or finding a little more overlap to decrease dynamic compression a little for a little extra detonation control. I’ve always regretted it also, since I’ve never had detonation issues with anything I’ve tried like this, a few iron headed engines pushing or in the low 10:1 compression range which seem to run fine even on 87…
- What are those cylinder heads painted with?
-
Vacuum to the crankcase is nothing new. Racers have been using vacuum pumps and converted smog pumps for some time now. I am using a belt drive emissions air pump reconfigured to pull air from the crankcase. It pulls about 7-9 in/hg on the crankcase which helps cut windage and allows the rings to seal better at higher rpms. Too much positive crankcase pressure is known to cause ring flutter which keeps them from sealing properly on the downward intake stroke and dilutes the intake charge.
Along those lines I have a smog pump off of an 80’s ford bronco that I modified for fittings that I’m planning on using the same way, I’m hoping that it is going to be close to a bolt in to the stock smog pump bracket, but I’m debating if I should try it or find another since the front bearing bore was a bit messed up and I had to use some JB weld to get a new bearing to seat correctly. What vacuum relief valve are you using?
- Do you actually have the valves unshrouded or are those just cuts from cutting the seats for the larger valves?
- Someone else already asked, but I didn’t see a response: what datalogger is that?
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Re: 356 RWHP TPI 310 Build
Originally Posted by flaming-ford
it makes perfect sense to me that a more efficient, smaller engine can make more power than a heavier less efficient engine....
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Re: 356 RWHP TPI 310 Build
I’m not sure why people expect such a big difference between a LS based engine and an SBC with nearly identical numbers… both are using a fast burn chamber, both have the same cooling and are very similar in design… the biggest difference is the 15* Vs 23* valves, and that’s more an airflow difference than anything else.
Let’s face it, your combination is only making enough HP to use about 200cfm of airflow or so, so you’ve got more flow than you need. Honestly, I’m a bit surprised that you’re doing it with SLP runners rather than stockers. I like the torque and HP curves… they’re _exactly_ what would be predicted if you do the math on a TPI intake… your cam choice and it’s tighter LSA doesn’t interfere with the natural powerband of the TPI, which is basically fat in the middle and keeps going till you run out of air (your combination that should be somewhere ~6500 from what I can tell). As I keep saying, if you want monstrous fat low end, say in the 2000rpm range, than you really need something different than a TPI.
Questions:
-How close are you on the detonation front? I’ve run combinations close to that before and always chickened out before pushing it quite that far, either a pulling back on the compression or finding a little more overlap to decrease dynamic compression a little for a little extra detonation control. I’ve always regretted it also, since I’ve never had detonation issues with anything I’ve tried like this, a few iron headed engines pushing or in the low 10:1 compression range which seem to run fine even on 87…
- What are those cylinder heads painted with?
.
-How close are you on the detonation front? I’ve run combinations close to that before and always chickened out before pushing it quite that far, either a pulling back on the compression or finding a little more overlap to decrease dynamic compression a little for a little extra detonation control. I’ve always regretted it also, since I’ve never had detonation issues with anything I’ve tried like this, a few iron headed engines pushing or in the low 10:1 compression range which seem to run fine even on 87…
- What are those cylinder heads painted with?
.
I ran the combination on 87 octane with a mild timing advance curve and ran a hotter curve on 93 octane. I even left the hotter advance curve in the chip and ran it on 87 a few times. The 7730 has a low-octane spark advance logic that retards the open throttle timing map under moderate-high loading and rpm if the knock sensor is picking up detonation. I saw the low-octane mode retard flag showing on some datalogs and just ran good gas in it. I also ran this combination on 104 octane E85 and it ran GREAT on it.
Huh??? The only thing I can figure is that you changed what you’re doing between responses?
Along those lines I have a smog pump off of an 80’s ford bronco that I modified for fittings that I’m planning on using the same way, I’m hoping that it is going to be close to a bolt in to the stock smog pump bracket, but I’m debating if I should try it or find another since the front bearing bore was a bit messed up and I had to use some JB weld to get a new bearing to seat correctly. What vacuum relief valve are you using?
- Do you actually have the valves unshrouded or are those just cuts from cutting the seats for the larger valves?
- Someone else already asked, but I didn’t see a response: what datalogger is that?
Along those lines I have a smog pump off of an 80’s ford bronco that I modified for fittings that I’m planning on using the same way, I’m hoping that it is going to be close to a bolt in to the stock smog pump bracket, but I’m debating if I should try it or find another since the front bearing bore was a bit messed up and I had to use some JB weld to get a new bearing to seat correctly. What vacuum relief valve are you using?
- Do you actually have the valves unshrouded or are those just cuts from cutting the seats for the larger valves?
- Someone else already asked, but I didn’t see a response: what datalogger is that?
I found the vacuum relief valve on Summit/Jegs but cannot remember the part-number, they market it as an adjustable vacuum relief valve
The cutter did cut into the chamber, but I performed some hand unshrouding as well. I did the top of the bores as well.
#78
Re: 356 RWHP TPI 310 Build
i just want to say this is one of the coolest engine builds i have seen and it has motivated me to try my own 305 TPI build. I like this idea of it because thats what engines came in these cars and its kind of cool to make power with what you have. How long did it take you to do the tuning? and how did you accomplish it? Did you use a wideband and just street tune it or did you do it on the dyno?
#79
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Car: 86 IROC Z
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Re: 356 RWHP TPI 310 Build
Man screw all these naysayers....you built a damn strong 305 and more power to you! I have similiar plans for my 87 z-28 305 retrofitted with a '7727 ECU and EBL flash system for tuning (I use tunerpro software and am just getting my feet wet with tuning...been a carb guy all my life...I'm currently enrolled at wyotech and am starting High Performance Powertrain here in a few weeks..she is gonna be my project in class) and your post helped me out tremendously...I appreciate everything you have posted and will be referencing it for my own build...356rwhp is outstanding man....hopefully I will be able to build a comparable motor now that I have some base specs to work with...thanks again!
Last edited by 3rdGenFreak1227; 06-08-2009 at 12:20 AM. Reason: added info
#80
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Car: 1989 Camaro RS
Engine: 2.8l v6
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Re: 356 RWHP TPI 310 Build
what exactly did you have done to ther heads? did you port them or did you take them to a machine shop? and just a figure of about how much did it cost for the heads to be ported and such if you didnt do it yourself?
Last edited by oxrabidus; 06-11-2009 at 04:44 AM.
#82
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Car: 1989 Camaro RS
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Re: 356 RWHP TPI 310 Build
could i use a chevy smog pump? or will a ford smog pump bolt into third gen brackets?
#84
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Car: 84 TA / 89 Formula
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Axle/Gears: 3.73 / 3.27
Re: 356 RWHP TPI 310 Build
this is a great thread indeed! congratz on those numbers, i know i'm a little late but i just found this thread this is most probably the most efficient 305 (N/A) build on this site!?
anyways, since summit updated their website structure, i re-did the links that stopped working for me here:
piston rings
harmonic balancer cover
intake valves
exhaust valves
greetz
ownor
anyways, since summit updated their website structure, i re-did the links that stopped working for me here:
piston rings
harmonic balancer cover
intake valves
exhaust valves
greetz
ownor
#86
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Car: 1987 GTA Vert & 1991 GTA 5 Speed
Engine: 87 GTA-L98 91 GTA LB9
Transmission: GTA-700R4 & GTA T5
Re: 356 RWHP TPI 310 Build
Ok its been a while and no comments on this build. The #s are incredible here.
Whats the latest. I skimmed thru all the post. Its possible I missed something. Has anything else been done with this wonder motor?
Whats the latest. I skimmed thru all the post. Its possible I missed something. Has anything else been done with this wonder motor?
#87
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Car: 1983 G20 Chevy
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Re: 356 RWHP TPI 310 Build
Its in a 1980 C10 with an Edelbrock Victor Jr Vortec 2bbl and a 454 TBI on top...... The van has a 383 TPI in it.........I mainly drive my 5.7 Hemi swapped Dodge Ram Quad cab though.
#88
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Car: 1989 G92 IROC-Z
Engine: 5 Liter 305
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Re: 356 RWHP TPI 310 Build
Fast, I see you live in Dallas. I live in Austin. Any chance you can help me out with a duplicate build? I would love to put this in my 85 LB9 Z28.
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Car: 1989 G92 IROC-Z
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Re: 356 RWHP TPI 310 Build
This thread is simply unbelievable. I still want to see more of this engine. 356RWhp out of an NA tuned port 350 is pretty amazing let alone a 305. I just cant get my head around this sucker. Do you have any more vids of this thing in action?
Also, why did you kill a bunch of the pics in this thread? I thought it was well documented and is there any way you can put them back up?
I sent you a PM a while back... ?
BTW: I am not being facetious. I like this build.... AAMOF, why did you take it out? Seemed like it was perfect for a van.
Also, why did you kill a bunch of the pics in this thread? I thought it was well documented and is there any way you can put them back up?
I sent you a PM a while back... ?
BTW: I am not being facetious. I like this build.... AAMOF, why did you take it out? Seemed like it was perfect for a van.
Last edited by TxTtopZ; 09-29-2010 at 06:39 PM.
#94
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Car: 1991 RS Camaro
Engine: 350 TBI
Transmission: 700R4
Axle/Gears: 3.42 Posi
Re: 356 RWHP TPI 310 Build
He probably took it out because he builds a new engine every month, lol.
The things that make this build possible are all the small details and tricks used. Larger valves, porting, roller rockers, pistons, quench space, intake mods, tuning, etc. All of these combined add up to extra gains which would not be possible just by slapping a pair of vortec heads on a stock shortblock.
The things that make this build possible are all the small details and tricks used. Larger valves, porting, roller rockers, pistons, quench space, intake mods, tuning, etc. All of these combined add up to extra gains which would not be possible just by slapping a pair of vortec heads on a stock shortblock.
#95
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Car: 1983 G20 Chevy
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Re: 356 RWHP TPI 310 Build
He probably took it out because he builds a new engine every month, lol.
The things that make this build possible are all the small details and tricks used. Larger valves, porting, roller rockers, pistons, quench space, intake mods, tuning, etc. All of these combined add up to extra gains which would not be possible just by slapping a pair of vortec heads on a stock shortblock.
The things that make this build possible are all the small details and tricks used. Larger valves, porting, roller rockers, pistons, quench space, intake mods, tuning, etc. All of these combined add up to extra gains which would not be possible just by slapping a pair of vortec heads on a stock shortblock.
Attention to detail is how you make power like this.
Ported heads
Oversize valves
Ported intake manifold
Header porting
1.6:1 full roller rockers
.040" quench
Windage control
Coatings
Balanced rotating assembly
Align bored block
Attention to tuning
My daily driver has gone 8.80s now, spinning the tires.
http://www.youtube.com/watch?v=6OjA5nq-BjQ
#97
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Car: 1983 G20 Chevy
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Axle/Gears: 14 bolt with 3.07 gears
Re: 356 RWHP TPI 310 Build
This thread is simply unbelievable. I still want to see more of this engine. 356RWhp out of an NA tuned port 350 is pretty amazing let alone a 305. I just cant get my head around this sucker. Do you have any more vids of this thing in action?
Also, why did you kill a bunch of the pics in this thread? I thought it was well documented and is there any way you can put them back up?
I sent you a PM a while back... ?
BTW: I am not being facetious. I like this build.... AAMOF, why did you take it out? Seemed like it was perfect for a van.
Also, why did you kill a bunch of the pics in this thread? I thought it was well documented and is there any way you can put them back up?
I sent you a PM a while back... ?
BTW: I am not being facetious. I like this build.... AAMOF, why did you take it out? Seemed like it was perfect for a van.
Here is the 312 with the 059s on it.
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Re: 356 RWHP TPI 310 Build
Get on the phone to the junkyards you may be able to get a whole vortec 305 for the cost of the heads and have a spare block. I know "round here" you can get a full motor for $150 if you pull it. Can't remember how much heads were last I was at the U-pull-it.
I'm going to copy it but use TBI next summer. I think these heads would love some TBI action and there's only one way to find out.
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Re: 356 RWHP TPI 310 Build
This motor would be awesome in a fbody.
Get on the phone to the junkyards you may be able to get a whole vortec 305 for the cost of the heads and have a spare block. I know "round here" you can get a full motor for $150 if you pull it. Can't remember how much heads were last I was at the U-pull-it.
I'm going to copy it but use TBI next summer. I think these heads would love some TBI action and there's only one way to find out.
Get on the phone to the junkyards you may be able to get a whole vortec 305 for the cost of the heads and have a spare block. I know "round here" you can get a full motor for $150 if you pull it. Can't remember how much heads were last I was at the U-pull-it.
I'm going to copy it but use TBI next summer. I think these heads would love some TBI action and there's only one way to find out.